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Hi Tineke,
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<div class="">My problem is that the triggers for the onset and the offset of the stimulus are the same…</div>
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<div class="">Message: 6<br class="">
Date: Tue, 10 May 2016 08:55:39 +0000<br class="">
From: "Snijders, T.M. (Tineke)" <<a href="mailto:tineke.snijders@donders.ru.nl" class="">tineke.snijders@donders.ru.nl</a>><br class="">
To: FieldTrip discussion list <<a href="mailto:fieldtrip@science.ru.nl" class="">fieldtrip@science.ru.nl</a>><br class="">
Subject: Re: [FieldTrip] two events per trial ?<br class="">
Message-ID:<br class="">
<span class="Apple-tab-span" style="white-space: pre;"></span><<a href="mailto:815A9820E75FBC4F96B7CD3A8089D11C378BF25F@exprd04.hosting.ru.nl" class="">815A9820E75FBC4F96B7CD3A8089D11C378BF25F@exprd04.hosting.ru.nl</a>><br class="">
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<div class="">Hi Cecile,<br class="">
<br class="">
One option is to run ft_definetrial two times.<br class="">
<br class="">
First you specify only your onset triggers as cfg.trialdef.eventvalue, with the correct cfg.trialdef.prestim, and a random cfg.trialdef.poststim (e.g. 1).<br class="">
Then you run<br class="">
cfg_begin=ft_definetrial(cfg)<br class="">
This gives you cfg_begin.trl which specifies the onset sample points of the trial in the first column, and the offset sample points of the trial in the second column (e.g. 1 second later, but you'll overwrite this later).<br class="">
<br class="">
Now you specify only your offset triggers as cfg.trialdef.eventvalue, with cfg.trialdef.prestim=0.<br class="">
You run:<br class="">
cfg_offset=ft_definetrial(cfg)<br class="">
This gives you cfg_offset.trl, with the first column being the offset sample points in your data.<br class="">
<br class="">
Now you make your final trl, in which you replace the second column of cfg_begin with the first one of cfg_offset<br class="">
<br class="">
trl=cfg_begin.trl;<br class="">
for i=1:size(cfg_offset.trl)<br class="">
trl(i,2)=cfg_offset.trl(i,1);<br class="">
end<br class="">
<br class="">
For ft_preprocessing you then give cfg.trl=trl.<br class="">
<br class="">
Best,<br class="">
Tineke<br class="">
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<br class="">
<br class="">
<br class="">
________________________________________<br class="">
From: <a href="mailto:fieldtrip-bounces@science.ru.nl" class="">fieldtrip-bounces@science.ru.nl</a> [<a href="mailto:fieldtrip-bounces@science.ru.nl" class="">fieldtrip-bounces@science.ru.nl</a>] on behalf of Cecile Issard [<a href="mailto:cecile.issard@etu.parisdescartes.fr" class="">cecile.issard@etu.parisdescartes.fr</a>]<br class="">
Sent: Sunday, May 08, 2016 11:30 PM<br class="">
To: <a href="mailto:fieldtrip@science.ru.nl" class="">fieldtrip@science.ru.nl</a><br class="">
Subject: [FieldTrip] two events per trial ?<br class="">
<br class="">
Hello,<br class="">
<br class="">
How can I specify that I have two events per trial (one for the onset and one for the offset of the stimulus) so that ft_definetrial finds the right (two times less) number of trials ?<br class="">
<br class="">
Best,<br class="">
<br class="">
C?cile<br class="">
<br class="">
?<br class="">
C?cile Issard<br class="">
PhD student<br class="">
Laboratoire Psychologie de la Perception<br class="">
CNRS UMR8242 - Universit? Paris Descartes<br class="">
45 rue des Saints-P?res<br class="">
75006 Paris<br class="">
<div class="">
<div class="">Cécile Issard</div>
<div class="">Doctorante</div>
<div class="">01.42.86.43.20</div>
<div class="">Laboratoire Psychologie de la Perception - UMR8242</div>
<div class=""><span style="font-family: arial, sans-serif; font-size: 13px;" class="">45 rue des Sts Pères</span><br style="font-family: arial, sans-serif; font-size: 13px;" class="">
<span style="font-family: arial, sans-serif; font-size: 13px;" class="">75270 Paris cedex 06</span><br style="font-family: arial, sans-serif; font-size: 13px;" class="">
<a href="http://lpp.psycho.univ-paris5.fr/index.php" target="_blank" style="font-family: arial, sans-serif; font-size: 13px;" class="">http://lpp.psycho.univ-paris5.fr/index.php</a>
<div style="font-family: arial, sans-serif; font-size: 13px;" class="">Labo bébé : <a href="http://recherche.parisdescartes.fr/LBB" target="_blank" class="">http://recherche.parisdescartes.fr/LBB</a></div>
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